Today, about one in three American kids and teens is overweight or obese, nearly triple the rate in 1963. With good reason, childhood obesity is now the No. 1 health concern among parents in the United States, topping drug abuse and smoking. Among children today, obesity is causing a broad range of health problems that previously weren’t seen until adulthood. These include high blood pressure, type 2 diabetes and elevated blood cholesterol levels. There are also psychological effects: Obese children are more prone to low self-esteem, negative body image and depression.

Excess weight at young ages has been linked to higher and earlier death rates in adulthood. Perhaps one of the most sobering statements regarding the severity of the childhood obesity epidemic came from former Surgeon General Richard Carmona, who characterized the threat as follows:

“Because of the increasing rates of obesity, unhealthy eating habits and physical inactivity, we may see the first generation that will be less healthy and have a shorter life expectancy than their parents."

When defining overweight in children and adolescents, it's important to consider both weight and body composition.

Among American children ages 2–19, the following are overweight or obese, using the 95^th percentile or higher of body mass index (BMI) values on the CDC growth chart:

• For non-Hispanic whites, 31.9 percent of males and 29.5 percent of females.
• For non-Hispanic blacks, 30.8 percent of males and 39.2 percent of females. 
• For Mexican Americans, 40.8 percent of males and 35.0 percent of females. 

The prevalence of overweight (BMI-for-age values at or above the 95th percentile of the 2000 CDC growth charts in children ages 6–11 increased from 4.0 percent  in 1971–74 to 17.0 percent in 2003–06. The prevalence of overweight in adolescents ages 12–19 increased from 6.1 percent to 17.6 percent. (NHANES, NCHS)

How do you prevent and treat overweight in children?

Reaching and maintaining an appropriate body weight is important. That's why recommendations that focus on small but permanent changes in eating may work better than a series of short-term changes that can't be sustained.

• Reducing caloric intake is the easiest change. Highly restrictive diets that forbid favorite foods are likely to fail. They should be limited to rare patients with severe complications who must lose weight quickly.
• Becoming more active is widely recommended. Increased physical activity is common in all studies of successful weight reduction. Create an environment that fosters physical activity.
• Parents' involvement in modifying overweight children's behavior is important. Parents who model healthy eating and physical activity can positively influence their children's health.

In treating most overweight children, the main emphasis should be to prevent weight gain above what's appropriate for expected increases in height. This is called prevention of increased weight gain velocity. For many children this may mean limited or no weight gain while they grow taller. Recommendations for maintaining weight should include regular physical activity and careful attention to diet to avoid too many calories. Factors predicting success are:

• including parents in the dietary treatment program
• strong social support of dietary intervention from others involved in preparing food
• regular physical activity prescription including social support

The importance of continuing these lifestyle changes well past the initial treatment period should be emphasized to the entire family. The healthiest way to change weight is gradually.

How is body fat measured?

Body mass index (BMI) assesses weight relative to height. It provides a useful screening tool to indirectly measure the amount of body fat. Weight in kilograms is divided by height in meters squared (kg/m²), or, multiply weight in pounds by 703, divide by height in inches, then divide again by height in inches. In children, the Centers for Disease Control and Prevention defines BMI-for-age at or above the 95th percentile as being overweight. It is important to assess the trend of the child’s BMI as this is an indirect measure of body fat.

The CDC recommendations for screening and assessing for obesity and overweight in children and adolescents mention the use of the triceps skinfold test for further evaluation when the BMI-for-age is  assessed above the 95^th percentile. Importantly, while triceps skinfold thickness can be unreliable, evidence suggests that children and adolescents assessed to have a skinfold measure greater than the 95th percentile are more likely to have excess body fat as opposed to increased lean body mass or large frame size.

Related AHA publications/programs:

• Understanding Childhood Obesity statistical sourcebook
• AHA Nutrition Center
• Heart Disease and Stroke Statistics Update
• NFL PLAY 60 Challenge: an in-school physical activity program of the AHA and the National Football League